Plate type heat exchange unit providing edge radiation



April 20, 1954 V PQLAD 2,676,001

PLATE TYPE HEAT EXCHANGE UNIT PROVIDING EDGE RADIATION Filed Sept. 5, 1950 IN V EN TOR.

720/745 FaZ zd Patented Apr. 20, 1954 PLATE TYPE HEAT EXCHANGE UNIT PROVIDING EDGE RADIATION Thomas H. Polad, Dowagiac, Mich., assignor to Rudy Manufacturing Company,

Dowagiac,

Mich., a corporation of Michigan Application September 5, 1950, Serial No. 183,110

7 3 Claims. 1

This invention relates to heat exchange units, and more particularly to heat exchangers such as condensers and the like employed as refrigeration systems.

One of the important objects of this invention is to increase the thermal efliciency of the heat exchanger, thereby enabling a smaller amount of material to effectuate the same heat transfer, at given temperature diiferences, as would be obtained with a much greater amount of material fabricated and assembled in the manner of conventional heat exchangers.

Another object of this invention is to secure a maximum cooling surface with a minimum amount of tubing and to so design and construct the heat exchanger that the tubing utilized will operate with a maximum of efficiency.

Another object of the invention is to provide a heat exchanger having heat transfer means embodying a maximum of edge area to thereby increase the efliciency of heat transfer from the plate structure to the air.

A further object of the invention is to so construct and assemble the plate structure that a maximum of plate edge area will be disposed in the high heat zone to thereby obtain a rapid transfer of heat through the plate edges and hence a marked efiicienny in the heat exchanger.

A still further object of the invention is to provide a plate structure of sheet form which may be inexpensively and rapidly manufactured, can be quickly and easily assembled, and will junction with a high degree of efiiciency.

Various other objects, advantages, and novel details of construction of this invention will be made more apparent as this description proceeds especially when considered in connection with the accompanying drawing, in which:

Figure l is an elevational view, partly broken away, of a heat exchange unit, constructed in accordance with this invention;

Fig. 2 is a sectional view taken substantially on the plane indicated by line 2-4 in Fig. 1; and

Fig. 3 is a view similarto Fig. 2 showing a slightly modified form of construction.

In the drawing, the reference character I indicates a single continuous fluid conducting conduit or tube bent into serpentine or zigzag iorm comprising return-bent portions I I connected by substantially straight portions I2. The tube thus formed may be D shaped in cross section as disclosed in the application for letters patent of T. H. Polad, Serial No. 179,469, filed August 15, 1950, and assigned to the assignee of the present invention.

The cooling or heat dissipating plate structure of this invention is in the form of a metal sheet I5 of reticulated configuration providing a plurality of relatively closely associated apertures I6 having a multiplicity of edges or edge areas H. The sheet or plate I5 may be produced in various ways. For instance, it may be made of expanded metal as herein illustrated or it may be made from an imperforate sheet with the desired number and shape of openings I6 punched or stamped out or otherwise formed therein. In any case, a structureof sheet or plate form is provided having a maximum amount of edge area to thereby increase the efficiency of heat transfer from the plate I5 to the air. The tube I0 and sheet I5 are bonded together in heat conductor relation in any suitable or Well known manner.

Opposed edges of the sheet I5 are preferably provided with angularly extending stiffening flanges I8 through which the free ends I9 of the tube I0 may extend. Supporting plates or brackets 20 of any desired form are provided for mounting the heat exchange unit on a support.

In Fig. 3 wherein a slightly modified form of construction is illustrated, the plate or sheet I5 of the fin structure is provided with a spaced parallel portion I5 of similar construction, the conduit or tube I0 being disposed between these plate portions l5 and I5 and bonded thereto in heat conductor relation. These plate portions may be formed separately or may, as shown, he formed from a single sheet return-bent as at 2| to provide the spaced plate portions I5 and I5. Obviously, with this construction the edge area I! is doubled.

It has been found that a greater transfer of heat from a plate structure to the surrounding air takes place from the edges of the structure than from the surfaces thereof, and that the rate of heat transfer substantially increases if the edges of the plate structure are disposed closely adjacent to or within the high temperature zones in close proximity to the conducting tubes. Full advantage of this phenomena has been attained with this invention. By reason of the perforated character of the fin sheet member, a maximum of edge area is obtained and this edge area is disposed closely adjacent to and within the high temperature zones surrounding the conducting tubes.

A heat exchanger constructed in accordance with this invention has many and varied uses. It may be used, in refrigeration systems, as either a condenser or an evaporator. It may be mounted in any position, either vertically, horizontally or angularly. As an evaporator, it may be used as a shelf or it may be shaped to form an enclosure in a freezing compartment or the like.

With this invention, it is possible to produce a heat exchanger, which is highly eificient, comprises a minimum number of. parts, and:.may be economically manufactured and assembled with facility.

What is claimed is:

1. A heat exchanger comprising, avafi'uid con;-

ducting tube member formed of return-b'ent=por-- tions connected by straight portions a11. a1,- ranged in a single continuoussurface, and a heat dissipating metal plate member secured in 15,,

heat conducting relation to one face of the return-bent portions and the-straightportionsoi said tube member, all of said return-bentportions being Within the periphery of' said plate member, said plate. member being provided with a pluralityoii rows ofclosely, spaced" apertures over its entire area" providing extended edge'areas located in close'gproximity to and in juxtaposition With said conducting tube member, eacli of the straight portions 'ofsaid tube member being'parailelto and spanningconsecutive'apertures in a row alongthe tube lengthwhich is locatedwithin the periphery of the 'p1ate-member.

2. A heat exchanger-as set forth in claim 1 including a pair of flanges mounted at opposite sides of said-plate member-adjacent to said return-bent portions; at least one end' of said tube member extending through one of said flanges in said pair.

3. A heat exchange unit comprising, a fluid conducting tube member formed of return-bent portions connected by straight portions all arranged. in a single continuous. surface, and a pair of spaced-parallel metal plate members arranged on opposite sides of said tube member and secured in heat conducting relation to the returnbent portions and the straight portions thereof, alliof said return-bent portions being within the peripheries of said plate members, said plate members .being provided with a plurality of rows oiclosely spaced apertures over their entire areas providing, extended edge areas located in close proximity to and in juxtaposition with said conducting tub'e member, each of the straight portionspf; said tube member being parallel to and spanning consecutive apertures in a row along the tube length which is located within the peripheries ofthe platermembers.

References'cited in the-file of this patent UNITED STATES PATENTS Number Name Date 1 1,697,600- Jack Jan. 1.1929 1,833,291 Kraenzlein et a1; Nov. 24,- 1931 1,880,877 Dick Oct. 4,- 1932 2,268;88'5 McCullough Jane 6', 194-2 2,471,582 Poole -MayBl, 1949 2,567,716 Kritzer Sept 11, 1951 

